On a shared network, an office device manages a plurality of terminal devices, and all terminal devices on the network share the network resources of the office device. All terminal devices are managed by the office device in a unified manner, and only a terminal device that passes the authentication by the office device can take part in service processing.
When carrying out multicast services on a shared network, generally the office device is used to copy multicast program video streams to implement multicast in the prior art. The specific scheme is as follows: Based on IGMP (Internet Group Management Protocol, Internet group management protocol) multicast protocol, the office device may identify how many users have requested playing of a same multicast program currently, copy the multicast program video streams to create a plurality of copies of the multicast program video streams according to the number of users who request playing of the multicast program, and provide copies of the multicast program video streams to a terminal device of each user that requests playing of the multicast program respectively through the shared network. In fact, this method implements multicast by bearing multicast packets in the unicast manner.
But in the foregoing method for implementing multicast on a shared network, every time a user adds a play request for a same multicast program, the office device needs to create one more copy of the multicast program video streams and provide the version for a terminal device of the user through the shared network, which occupies a large part of downlink bandwidth.